Safety closure

ABSTRACT

The invention relates to a safety closure for a container mouthpiece having an external screwthread and a cap having an internal screwthread mating therewith and an insertable stopper, and in which the stopper and a top portion of the screwcap are provided with complementary members which co-operate to function in the manner of a bayonet catch whereby the screwcap acts as a means for withdrawing the stopper from the mouth of the container and such that on effecting the withdrawal the stopper remains in attachment with the screwcap.

tinite Claasen States Patent 1191 [1111 3,831,796 [451 Aug. 27, 1974 1 1 SAFETY CLOSURE [76] Inventor: Antonius Bernardus Claasen,

Sperwerlaan 4, Leende (NB), Netherlands [22] Filed: Aug. 23, 11972 [21] App]. No.: 283,166

[30] Foreign Application Priority Data Aug. 25, 1971 Netherlands 4. 7111693 [52] US. Cl. 215/9, 215/55 [51] int. C1. A61j 1/00, B65d 55/02 [58] Field of Search 215/9, 55, 50, 44

[56] References Cited UNITED STATES PATENTS 3,409,159 11/1968 Velt 215/55 X 3,704,802 12/1972 Schultz ..215/9 Primary Examiner-George T. Hall Attorney, Agent, or Firm-Brooks Haidt & Haffner [57] ABSTRACT The invention relates to a safety closure for a container mouthpiece having an external screwthread and a cap having an internal screwthread mating therewith and an insertable stopper, and in which the stopper and a top portion of the screwcap are provided with complementary members which co-operate to function in the manner of a bayonet catch whereby the screwcap acts as a means for withdrawing the stopper from the mouth of the container and such that on effecting the withdrawal the stopper remains in attachment with the screwcap.

10 Claims, 2 Drawing Figures PAIENIEB wszmu FIG? SAFETY CLOSURE This invention relates to improvements in safety closures for container mouthpieces having an external screwthread.

Safety closures of the type comprising two parts are well-known and have been developed for use with containers such as bottles, flasks, tubes and the like employed in the storage of toxin containing preparations, medicines and generally dangerous materials which are subjected to injudicious use. Such a closure relies on its inherent safeness through the difficulty experienced in the opening of the container and such that access to the contents is, to all intents and purposes, unattainable especially to small children.

One prior safety closure comprises a cap having an internal screwthread mating with the external screwthread of the mouthpiece, and an insertable stopper, the stopper and the cap being provided with complementary threaded means for the removal and re-insertion of the stopper by means of the cap. One disadvantage of this construction is that when the stopper has been reinserted in the mouthpiece by means of the cap, difficulties are experienced in disengaging the cap from the stopper in that the latter tends to rotate along with the cap, especially if the container is filled with a liquid having a lubricating effect.

In another well-known type of safety closure, the mouthpiece of the container as well as being provided with an external screwthread is provided with an internal screwthread which is arranged to engage a mating screwthread on the stopper. In such an arrangement the stopper is intended to be screwed into and out of the container. Application of such an arrangement to, for example, a bottle having an external screwthread on the mouthpiece only makes it necessary to provide an adapter having an internal screwthread and which must be introduced between the inner wall of the mouthpiece and the external surface of the stopper. In such an example there is the suggestion of a three-part safety closure in which the stopper, with the exception of a recess therein, is moreover of a solid construction.

One object of the present invention is the provision of a safety closure of the previously described types in which the quoted disadvantages are eliminated, which is of simple construction without detriment to its effectiveness, and in which the stopper will suffice for its purpose with use of very little material.

According to one aspect of the present invention therefore there is provided: A safety closure for a con tainer mouthpiece having an external screwthread, which said safety closure comprises a cap having an internal screwthread mating with the said external screwthread of the mouthpiece, and an insertable stopper, and which in the region of the open end of the mouthpiece the stopper and a top portion of the screwcap are provided with complementary members which function in the manner of a bayonet catch whereby the screwcap may be employed as a means for withdrawing the stopper from the container mouth.

A characterising feature of the safety closure to be described herein is that complementary members are employed which operate in the manner of a bayonet catch. In such a safety closure the stopper need not be screwed into the mouth of the container but may be pushed in. In a preferred embodiment of the invention, in a region close to the open end of the cylindrical stop per radially inward directed projections are arranged to co-operate with cam-like portions of the screwcap extending from a top portion thereof and in such a manner that with the stopper removed from the container it remains attached to the screwcap and from which it cannot roll away through separation.

Through the use of projections extending from the circumferential surface of the stopper, the latter can be inserted into the mouth of the container to be securely held therein by friction between both, and such a stopper can be applied to containers having a smooth inner wall. Furthermore the stopper can be pushed some distance into the mouth of the container by an internal collar of the screwcap and with the certainty that it cannot be removed without the aid of the cam-like portions of the screwcap.

In view of the proposed design, the stopper need not be of solid construction, but in consideration of the need for a frictional gripping force to exist between the mouth of the container and the stopper it is even recommendable that the stopper should be radially deformable. As opposed to being of solid construction the stopper employed in the presently to be described arrangement may take the form of a hollow cylinder closed with a transverse wall portion.

The problem of spillage is always present with fluid containing flasks for example. In the arrangement to be described this problem may be overcome by providing a cylindrical sleeve between the container mouth and the stopper, and which sleeve incorporates a pouring lip which extends radially over the rim of the container mouth.

To ensure that the cylindrical sleeve is not removed from the container mouthpiece when the stopper is withdrawn, the sleeve may be provided with one or more retaining members at its lower end. These retaining members may comprise a perforated partition that is arranged to be accommodated in a groove at the lower end of the sleeve and which internal groove is axially co-incident with an integral external annular collar which is separated into segments by a series of axial slots in the sleeve. These segments, on insertion of the cup-like member into the mouth of the container, are

displaced radially inwards through the agency of the slots, and when the member is fully in place in the mouth of the container the segments at the lower end are free of restraint by the wall of the mouth and thus are permitted to spring back to their original positions to grip an interior portion of the container clear of the mouth, i.e., collectively the segments formed by the separated collarassume a diameter greater than the diameter of the mouth. The perforated partition is then inserted to assume a position in the annular internal groove to maintain the segments in a position to retain the cup-like member from withdrawal with the stopper. The groove in the cup-like member may be formed by an internal annular collar and a number of axially disposed webs along which the perforated partition can slide during assembly due to the tapered form of the webs.

The invention will be better understood with refer ence to the accompanying drawings which show preferred embodiments of the invention and in which:

FIG. ll shows a cross-sectioned elevation of one application of a two-part safety closure and,

FIG. 2 shows a cross-sectioned elevation of another application of a two-part safety closure.

Referring in the first instance to FIG. I. this figure shows, on the left-hand half thereof, a container in the closed condition; and on the right-hand half thereof the container with the cap removed prior to removing the stopper.

The container mouth I has a smooth cylindrical inner wall 2 and is provided with a screwthread 3 on the external wall which mates with the internal screwthread 4 of a screwcap 5. The screwcap 5, formed of a suitable plastics material, is provided with a top portion 6 which incorporates radially outward extending cam-like portions 7. This screwcap forms one part of a two-part safety closure, the other part is formed by a stopper 8, likewise formed of a suitable plastics material, such as a polyamide, and which is arranged to frictionally fit in the smooth inner wall 2 of the container mouthpiece I.

The stopper is in the form of a hollow cylinder having a closed end, the hollow cylindrical portion is designated 9 and the closed end 10. The outer circumferential wall of the cylinder is provided with projections in the form of integral axially spaced collars ill and at the upper end a number of radially inward extending projections which are formed by the portions remaining of a radial flange 12 after being sloted at a number of positions such as designated 13. These portions are complementary to and are equal in number to the cam-like portions 7 extending radially outward from the top portion 6 of the screwcap S. This arrangement is such that the cam-like portions 7 can pass through the slots I3 in the flange 12 of the stopper 8 when the cap (in the removed condition and turned upside down) is lowered toward the stopper 8, on completion of this passage the screwcap the latter is turned to bring the cam-like portions under the respective ones of the radially inward extending projections of the flange 12. By using the screwcap as a tool the stopper can then be withdrawn from the mouthpiece 1 and the former will remain in attachment with the latter.

In order to ensure that the stopper 8 penetrates deep enough into the mouth of the container on insertion therein, and further to ensure that it cannot be removed without the aid of the screwcap by way of the cam-like portions thereon engaging the projections of the stopper, the screwcap is provided with an internal collar I5 which forces the stopper below the rim of the mouthpiece I when the cap 5 is screwed tight.

It will be evident from the embodiment of the safety closure shown in FIG. 2, that a closure according to the present invention is not only applicable to containers, such as bottles, provided with mouthpieces having smooth inner walls, but also to containers primarily used in pharmaceutical fields which incorporate an insert or sleeve provided with a pouring lip.

Such a container with an insertable sleeve M having a pouring lip is shown in FIG. 2. The sleeve is formed of a suitable polymeric material such as a polyamide. The stopper 8 thereof in this example differs from the stopper 8 shown in FIG. I only to the extent that the stopper 8 of FIG. 2 incorporates no friction collars and fits into the sleeve 14 instead of into the mouthpiece 1. If desired friction collars such as 11 in FIG. ll may be provided for the stopper 8' of FIG. 2, by proper choice of dimensions of the top portion 6 of the screwcap 5 and the internally disposed slotted annular flange 12 of the stopper.

In order to ensure that the sleeve 14 is not withdrawn from the mouthpiece I with the stopper 8' there are provided retaining members. These comprise a perforated partition I6 that is arranged to be accommodated in an internal annular groove 17, which groove is axially co-incident with an external and integral collar 19, which is separated into segments by a series of slots 18 in the sleeve 14. These segments, on insertion of the sleeve 14 in the container mouthpiece, are displaced radially inward such that they pass down the mouthpiece 1 to reach a position in which they are clear of the mouthpiece 1 and then assume their original positions to engage an interior portion of the container and in which position they are fixed by the insertion of the previously mentioned perforated partition 16 into the groove 17, which is formed by an inner annular collar 21 and a series of tapered web portions 20 which are spaced around the interior of the sleeve I4. Advantageously, the perforated partition I6 is formed integrally with the sleeve 14 at the level of the pouring lip, i.e., attached to the sleeve with relatively weak web portions, which are subsequently broken when the sleeve is installed and the partition I6 is displaced downwardly by means of a plunger until it is lodged in groove 17. In the last described embodiment the screwcap 8 can also be provided with an internal collar such as 15 shown in FIG. 1 to push the stopper 8' sufficiently deep into the mouthpiece l of the container on assembly. The stopper may equally well include a rim on its upper end such that it blends in with and over the rim of the sleeve. The embodiment shown in FIG. 2 has an advantage over the embodiment shown in FIG. I inasmuch that the stopper 8 cannot be pushed into the mouthpiece 1 too deep such that it falls into the container and whereby the contents can be released through absence of the stopper in its correct position.

We claim:

1. A safety closure for a container mouthpiece having an external screwthread, said safety closure comprising a cap having an internal screwthread mating with said external screwthread of the mouthpiece, and an insertable stopper, said stopper in normal closed position having its upper end adjacent a rim of said mouthpiece, said upper end of the stopper and a top portion of the screwcap each having complementary members cooperating in the manner of a bayonet catch for use of the screwcap as a means for withdrawing the stopper from the container.

2. A safety closure of a container as claimed in claim 11, wherein the stopper is cylindrical in form and has an open end, said complementary members being in the form of projections which extend radially inward from the cylindrical stopper and in the form of cam-like portions which extend radially outward from the said top portion of the screwcap and being arranged in such a manner that on withdrawal the stopper remains in attachment with the screwcap.

3. A safety closure for a container mouthpiece as claimed in claim I wherein the said stopper is provided with projections on its circumference.

4 A safety closure as claimed in claim 3, characterized in that said projections comprise a number of circumferential collars axially spaced along the length of the stopper.

5. A safety closure for a container mouthpiece as claimed in claim I wherein the said stopper is in the form of a hollow cylinder one end of which is closed by a partition.

6. A safety closure for a container mouthpiece as claimed in claim 1 wherein said screwcap incorporates an internal collar which acts to insert the stopper into the mouthpiece of the container below the rim thereof.

7. A safety closure for a container mouthpiece as claimed in claim 1 and including a cylindrical sleeve which is fitted between the stopper and the mouthpiece and a pouring lip which extends over the rim of the mouthpiece.

8. A safety closure for a container mouthpiece as claimed in claim 7, wherein the cylindrical sleeve is a cup-like member including a number of retaining members at the lower end thereof, by which means the cuplike member is retained in the mouthpiece of the container.

9. A safety closure for a container mouthpiece as claimed in claim 8, characterized in that the said retaining members are formed by a perforated partition for insertion into a groove in the lower end of the sleeve which is axially co-incident with an external collar thereon which is separated to form segments by a series of axial slots in the cup-like member and which said segments on insertion of the cup-like member into the container are displaced radially inward such that they pass down the said mouthpiece to reach a position in which they are clear of the mouthpiece and assume their original positions to engage an interior portion of the container and in which positions they are fixed by the insertion of the said perforated partition into the said groove.

10. A safety closure for a container mouthpiece as claimed in claim 9, characterized in that said groove is formed by an annular collar and a number of axially disposed webs, formed on the inner wall of the sleeve. =l l l l 

1. A safety closure for a container mouthpiece having an external screwthread, said safety closure comprising a cap having an internal screwthread mating with said external screwthread of the mouthpiece, and an insertable stopper, said stopper in normal closed position having its upper end adjacent a rim of said mouthpiece, said upper end of the stopper and a top portion of the screwcap each having complementary members co-operating in the manner of a bayonet catch for use of the screwcap as a means for withdrawing the stopper from the container.
 2. A safety closure of a container as claimed in claim 1, wherein the stopper is cylindrical in form and has an open end, said complementary members being in the form of projections which extend radially inward from the cylindrical stopper and in the form of cam-like portions which extend radially outward from the said top portion of the screwcap and being arranged in such a manner that on withdrawal the stopper remains in attachment with the screwcap.
 3. A safety closure for a container mouthpiece as claimed in claim 1 wherein the said stopper is provided with projections on its circumference.
 4. A safety closure as claimed in claim 3, characterized in that said projections comprise a number of circumferential collars axially spaced along the length of the stopper.
 5. A safety closure for a container mouthpiece as claimed in claim 1 wherein the said stopper is in the form of a hollow cylinder one end of which is closed by a partition.
 6. A safety closure for a container mouthpiece as claimed in claim 1 wherein said screwcap incorporates an internal collar which acts to insert the stopper into the mouthpiece of the container below the rim thereof.
 7. A safety closure for a container mouthpiece as claimed in claim 1 and including a cylindrical sleeve which is fitted between the stopper and the mouthpiece and a pouring lip which extends over the rim of the mouthpiece.
 8. A safety closure for a container mouthpiece as claimed in claim 7, wherein the cylindrical sleeve is a cup-like member including a number of retaining members at the lower end thereof, by which means the cup-like member is retained in the mouthpiece of the container.
 9. A safety closure for a container mouthpiece as claimed in claim 8, characterized in that the said retaining members are formed by a perforated partition for insertion into a groove in the lower end of the sleeve which is axially co-incident with an external collar thereon which is separated to form segments by a series of axial slots in the cup-like member and which said segments on insertion of the cup-like member into the container are displaced radially inward such that they pass down the said mouthpiece to reach a position in which they are clear of the mouthpiece and assume their original positions to engage an inteRior portion of the container and in which positions they are fixed by the insertion of the said perforated partition into the said groove.
 10. A safety closure for a container mouthpiece as claimed in claim 9, characterized in that said groove is formed by an annular collar and a number of axially disposed webs, formed on the inner wall of the sleeve. 